I have a set of external hard drives that I use for backups of my photos and images. They were formatted as EXT4 and setup with encryption from a laptop running Ubuntu 10.04 - and I've had no problems with mounting and running rsync on my image folders to backup new files to the disks.
I recently acquired a netbook for travel purposes, and am trying to get the drives to also work on this so I can make backups while on holiday. The netbook is running Ubuntu 11.04.
When I first plugged in one of the drives, I was asked for the password, which I entered, and the disk activity light started blinking, but no file window opened as I expected. However, I did not get any error messages, either.
When I opened a file window, I could see the volume listed as "Backup Alpha" (the disk's name) but when I tried to open it, I received the error:
Unable to mount "Backup Alpha" /dev/dm-0 is mounted
When I try to unmount the drive, by right-clicking and selecting the "safely remove drive" option, I get the message:
Unable to stop 500 GB Hard Drive One or more block devices are holding /dev/sdb
One problem I did have when initially trying to access the drive was that
cryptsetup had not yet been installed on the computer, and so the first time I tried to enter a password and access the drive failed.
I found a way to disable automount, but now I'm having problems manually mounting the drive:
$ sudo mount /dev/sdb /media/backup -o uid=1000,gid=1000,utf8,dmask=027,fmask=137 mount: unknown filesystem type 'crypto_LUKS'
I found some help at http://ubuntuforums.org/showthread.php?t=868681 and tried:
$ mkdir /media/backup $ modprobe dm-crypt $ cryptsetup luksOpen /dev/sdb backup $ vgchange -ay $ mount /dev/("volume group name") /media/backup
The problem is that
vgchange doesn't output any volume groups, and I still can't mount